1. Field of the Invention
The present invention generally relates to a liquid crystal display apparatus and a manufacturing method thereof.
2. Description of the Related Art
FIG. 1 is a block diagram showing the configuration of a data driving unit in a conventional liquid crystal display apparatus. As shown in FIG. 1, the data driving unit in the conventional liquid crystal display apparatus includes data drivers DV1 through DVn. Each of the data drivers DV1 through DVn takes in a data signal DATA according to a supplied display start signal, and supplies an activated display start signal EOUT to a data driver situated at the following stage. In this manner, the data signal DATA is taken in one after another by the data drivers DV1 through DVn that are provided in a parallel arrangement. In addition, as shown in FIG. 1, a clock signal CLK, a latch pulse LP, and a reference voltage Vref are supplied to each of the data drivers DV1 through DVn.
FIG. 2 is a block diagram showing a configuration of the data driver DV1 shown in FIG. 1. The data drivers DV2 through DVn shown in FIG. 1 have the same configuration as the data driver DV1.
As shown in FIG. 2, the data driver DV1 includes an output amplifier 1, a D/A converter 3, a latch circuit 5, a shift register 7, and a clock controller 9. Here, the source line SL is connected to the output amplifier 1, and the D/A converter 3 is connected to the output amplifier 1. Further, the latch circuit 5 is connected to the D/A converter 3, and the shift register 7 is connected to the latch circuit 5. Further, the clock controller 9 is connected to the shift register 7. In addition, the reference voltage Vref is supplied to the D/A converter 3, and the data signal DATA is supplied to the shift register 7. Furthermore, the clock controller 9 receives the display start signal EI, the clock signal CLK, and a latch pulse, and outputs the display start signal EOUT.
Therefore, in the conventional liquid crystal display apparatus which has the above configuration, since the clock signal CLK was supplied to each of the data drivers DV1 through DVn with no regard to the data signal DATA, there was a problem of the clock signal CLK causing aggravation of an EMI (electromagnetism interference noise) level and increase in power consumption.
In recent years, the technology of electric and electric devices has been rapidly advancing. However, overheating and fire hazards of electric apparatuses by harmonics in a low frequency domain and noise interference to TV sets and the like in a high frequency domain have been caused. Electromagnetic obstacles such as these pose a common problem of every country in the world. Therefore, at present, the necessity for a measure against the electromagnetic interference (EMI measures) is increasing.
On the other hand, recently, a TFT-liquid-crystal display apparatus has become larger with finer scales and higher contrast ratios, for use as a monitor of a personal computer or TV picture display. In such applications, it is required that the liquid crystal display apparatus is viewable from all directions.
Here, the MVA (Multi-domain Vertical Alignment) type liquid crystal display apparatus has been devised as technology of realizing a liquid crystal display apparatus with an extensive view angle. That is, in an MVA type liquid crystal display apparatus, as shown in FIG. 3, it is prepared so that transparent electrodes 11 to which bank-like dielectric structures 13 are formed will face each other, and a liquid crystal layer which includes liquid crystal molecules 15 is installed between the two transparent electrodes 11.
Further, as shown in FIG. 3-(a), when a voltage is not applied between the transparent electrodes 11 which face each other, the liquid crystal molecules 15 are oriented perpendicularly, and if a voltage is applied, as shown in FIG. 3-(b), they will incline in directions that are predetermined for every four domains. In this manner, view angle characteristics of the four domains are mixed, enabling to provide a large viewing angle.
Here, in the MVA type liquid crystal display apparatus, as shown in the contrast diagram of FIG. 4, a contrast (CR) value of 10 is realized at 80 degree angles both vertically and horizontally for monochrome viewing.
In addition, as structure of the MVA type liquid crystal display apparatus, a slit may be formed on the electrode instead of the dielectric structure, and a combination of a substrate with the slit and a substrate with the dielectric structure may be used as the structure. Further, a combination of a dielectric structure and a slit may be formed on one substrate.
However, when the display of a middle tone, for example, a female picture as shown in FIG. 5, is displayed, a problem arises that the whole picture will become white and the contrast is lost at a lower view angle as shown in FIG. 6.